There is an easy way to prevent showing author metadata on a post. The part of a twenty sixteen WordPress installation that generates the author metadata in posts is inside the template-tags.php.
There is this function twentysixteen_entry_meta() from which you can just delete or comment out the if ( 'post' === get_post_type() ) part.
I mentioned before that theme customisations should be handled by creating child themes. This time, again, I didn’t bother with that.
This is the result:
